Im doing a problem with variable frictional forces.(adsbygoogle = window.adsbygoogle || []).push({});

My main equation is -mkv^2=F . We are to assume the force driving the object remains constant, kinda like a boat on the lake full bore.

So, I set my F=ma equation up.

-mkv^2=m(dv/dt)

Next I removed m and inverted both equations to solve for dt.

-dv/(kv^2)=dt

Next I intetegrated both sides seperately. I was taught to use a "dummy variable" by marking v and t somehow. I simply chose to use a superscript prime marking on my paper. anyhow... Ill use a little v for real velocity and big V for dummy velocity.

(1/kV)|0 to v = t

Isnt that (1/kv) - (1/0) ?

This equation doesnt solve nicely. In my setup I am given the equation for velocity and only asked to show how I got it.

V=Vo / (1 + Vo*kt)

Please help... I posted part of this problem over in classical when I had a different problem with it, so please dont flame me for double posting or spamming the board. If thats your opinion I couldnt care less.

TIA to anyone who helps!

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# Homework Help: Velocity based frictional force equations

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